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MIT Solar Towers Beat Solar Panels By Up To 20x

Posted by timothy on from the if-they-had-pants-they'd-have-been-beaten-off dept.

An anonymous reader writes "A team of MIT researchers has come up with a very different approach to solar collectors: building cubes and towers that extend solar cells upward in three-dimensional configurations. The results from the structures they've tested show power output ranging from double to more than 20 times that of fixed flat panels with the same base area (abstract, full pre-print). The biggest boosts in power were seen in the situations where improvements are most needed: in locations far from the equator, in winter months and on cloudier days."

7 of 159 comments (clear)

  1. Picture... by Anonymous Coward · · Score: 5, Informative

    Picture available here. It's a solar pancake!

    1. Re:Picture... by uigrad_2000 · · Score: 4, Informative

      The Ion cannon article was featured on Slashdot two weeks ago.

      I think a better way to state it, would be to say that efficiency per square foot of ground used is not important, unless the cost of the cells come down.

      Now that there is word of a new manufacturing process to reduce cost, two weeks later, we find an article about how to arrange low-cost cells.

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    2. Re:Picture... by fast+turtle · · Score: 4, Informative

      Did you RTFA? I happened to do so having caught it a couple of days ago. The interesting element to this design is the early/late (dawn/dusk) power generation as the current method doesn't get enough solar incidence to generate anything until 3 hours after sunrise/3 hours before sunset. That's 6 hours of production that's being missed, which is why this design reaches 15-20x the generated power of conventional flat panels.

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  2. paper link by Trepidity · · Score: 4, Informative

    As seems depressingly common in science journalism, they vaguely mentioned the existence of a paper, but don't actually give the title or (dare we hope) a hyperlink to the paper. At least they did mention the name of the journal it was published in.

    In any case, the paper is "Solar energy generation in three dimensions." If you're at a university with a subscription the official version (not open-access) is here. There is also an open-access preprint version at the arXiv.

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  3. But much harder to set up by Hentes · · Score: 5, Interesting

    Most people use solar panels because they can be comfortably put on rooftops. If someone has enough room for these 3D structures they could just install a Sun tracking system that's even more efficient.

  4. misleading by demonbug · · Score: 5, Insightful

    20x output (compared to a flat panel with the same footprint).

    Not really news. This is like excitedly proclaiming that a 20 story building has nearly 20 times the floorspace of a single story building with the same footprint. Uh, no shit? (Or that a 20 story building receives more insolation than a 1-story building; hmm, you think maybe it has a lot more surface area?) I also like that they hand-wave away the fact that it costs significantly more per unit output by saying that cells are getting cheaper. Great.

    Not that there aren't uses - it absolutely makes sense to go this route where you have limited footprint space - but it just doesn't seem at all revolutionary. I guess if you tack the letters M-I-T onto a press release it instantly becomes newsworthy.

  5. Re:Duh by ILongForDarkness · · Score: 5, Interesting

    I agree about shadow effects. More comes into play though since more angles will be approximately normal to the panels more angles of light will still be in an effective region of the panel for collecting. In winter in the non-tropical regions the sun's maximum height can be pretty low in the sky giving you a very oblique angle to fixed panels against a roof (assuming a shallow slope on the roof). Making these suckers stick up means that the crossection exposed to the sun is larger even if the sun is lower in the sky.

    That said two problems I see:

    1) Roof top intallation will be weight. I have panels on my roof and they are about 100lb per sq yard. Stack twenty together and you'd be looking at 2000lb per sq yard. Not a good thing for the roof.

    2) Ground based panels: you can put the panels on stands that can be adjusted, heck they can be motorized so they can track the sun through the day AND through the seasons. So why exactly would you by ~20X more panels (at about 200 a pop) when a $50 motor per panel (guessing), or an adjustable stand that someone goes out and tilts every month or so can have the same affect?